Indigenous Knowledge and Utilisation of Strychnos spinosa Lam. in Sub-Saharan Africa: A Systematic Review of Its Medicinal, Nutritional, and Cultural Significance

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Title

It would be better to make the title clearer. Such as “Indigenous Knowledge and Utilization of Strychnos spinosa Lam. in Sub-Saharan Africa: A Systematic Review of Its Medicinal, Nutritional, and Cultural Significance”

Abstract

· The review highlights the lack of analysis on S. spinosa's nutritional and bioactive compounds, suggesting a gap but not proposing specific research methodologies to address it.

· The geographical bias towards Southern Africa limits the understanding of the plant’s significance across the entire sub-Saharan region; research in underrepresented areas is needed.

· Semi-structured interviews are commonly used in studies, which may introduce biases; a more triangulated approach with expert consultations and laboratory analysis would strengthen the findings.

· The review mentions cultural uses but does not explore them in depth; a deeper look into the plant’s role in local ceremonies and folklore would enrich the understanding.

· There is no mention of sustainability concerns or conservation status of S. spinosa; research should focus on sustainable harvesting practices to protect the plant for future use.

· The review could benefit from an interdisciplinary approach combining ethnobotany, pharmacology, and environmental science to provide more holistic insights.

· A quantitative analysis of the studies reviewed would provide more empirical data on the plant's medicinal effectiveness.

· Ethical considerations regarding the use of indigenous knowledge, such as intellectual property and benefit-sharing, should be addressed to respect local communities.

Introduction

· The introduction highlights the potential of Indigenous Knowledge (IK) in environmental conservation, but it could further discuss how IK can complement modern science in addressing global environmental issues.

· While emphasizing the role of IK in rural communities, the review does not address the challenges of preserving and transmitting this knowledge, especially in the face of urbanization and globalization.

· The discussion on Strychnos spinosa emphasizes its uses, but it would benefit from a more detailed analysis of how its utilization varies across different African cultures and regions.

· The review mentions the plant's high nutritional content and potential for improving food security, but it lacks a deeper exploration of how these benefits translate into practical applications at the community level.

· The statement that S. spinosa is classified as "Least Concern" on the IUCN Red List could be misleading, as the review then suggests that its widespread use poses a threat to its long-term availability. A clearer discussion on the reasons for its classification and the risks it faces would be beneficial.

· The paper addresses sustainable harvesting practices, but it could offer more concrete recommendations or examples from other regions or species that have successfully implemented such practices.

· While the review calls for integrating local communities into conservation efforts, it does not discuss the challenges or barriers to achieving this, such as lack of resources or conflicting priorities.

· There is a significant focus on the medicinal and nutritional benefits of S. spinosa, but the review does not sufficiently address the cultural and spiritual significance of the plant, which may play a role in its conservation.

· The need for sustainable practices is acknowledged, but the paper would be stronger if it included case studies or evidence of successful conservation efforts involving S. spinosa or similar species.

· The review suggests that there is a gap in understanding the traditional uses of S. spinosa but does not mention the importance of involving local communities in future research, ensuring that their knowledge is respected and ethically used.

Material and Methods

· The use of the PRISMA 2020 statement is appropriate for ensuring a systematic and transparent review process, but the methods could benefit from a clearer explanation of how the inclusion criteria were defined, particularly regarding the type of studies considered (e.g., peer-reviewed articles vs. grey literature like theses and dissertations).

· While databases like JSTOR, ScienceDirect, PubMed, and Google Scholar are commonly used, the review could be strengthened by considering additional sources, such as local or regional journals, indigenous knowledge repositories, or government publications, to capture a broader range of relevant studies.

· The review mentions the use of search terms like "Indigenous knowledge" and "phytochemical analysis," but it would be useful to specify whether additional keywords related to S. spinosa (e.g., "bushman's poison tree," "kaffir orange") were also used to ensure comprehensive coverage of studies on the plant.

· The inclusion criteria specify that studies must be conducted in Africa, but it would be helpful to further explain the rationale behind focusing exclusively on African studies. Are there regional variations in the use or conservation of S. spinosa that warrant this limitation?

· The methodology section mentions the collection of studies for "in-depth evaluation," but it does not clarify the process of study selection or the criteria for determining quality or relevance. More details on how studies were evaluated and categorized would enhance the transparency of the review.

· The use of a variety of study types, such as theses and dissertations, is commendable for capturing grey literature, but the review should discuss how potential biases or limitations in these types of sources were addressed, especially in terms of methodology or peer review.

· It is unclear whether studies in languages other than English were included. If the review was limited to English-language sources, this could introduce a bias, especially since indigenous knowledge is often transmitted in local languages. Including a broader linguistic scope would provide a more inclusive review.

Results and discussion

· The study focuses heavily on ethnobotanical surveys and does not delve deeply enough into experimental or quantitative analysis, such as phytochemical screening, which is crucial for confirming the therapeutic potential of S. spinosa.

· The review highlights the importance of documenting traditional knowledge, it lacks specific details about how the findings can be practically applied to improve conservation or community health.

· The exclusion of studies due to language barriers or lack of full-text access may have led to the loss of potentially valuable information, especially from regions where S. spinosa is more commonly used.

· The study mentions a variety of plant parts being used, but does not provide a comparative analysis of the efficacy of different parts or explore the regional differences in preparation methods and their impact on medicinal use.

· The absence of information about the number of participants in the studies and the sample size reduces the overall reliability and validity of the findings related to the efficacy of S. spinosa in treating specific ailments.

· Although the study addresses the need for research into the socio-ecological impacts of harvesting S. spinosa, there is no concrete framework proposed to assess or mitigate these impacts, which is essential for sustainable resource management.

· A deeper exploration of the economic viability and commercialization of S. spinosa could strengthen the argument for its potential to address food insecurity, as the current analysis mainly focuses on its medicinal uses.

· There is insufficient discussion on the potential risks or toxicity of S. spinosa, which is critical when considering its widespread use in traditional medicine and its potential for commercialization.

Conclusion

· Lacks specificity on which bioactive compounds need further investigation.

· The plant’s use for gastrointestinal conditions and fever treatment could be linked to specific diseases for better clarity.

· Cultural practices are mentioned but need more detail on regional differences.

· No mention of potential risks or toxicity of S. spinosa.

· Calls for collaboration without concrete examples or strategies.

· Ignores limitations of current research, such as data accessibility and quality.

· Fails to suggest specific methods for integrating traditional knowledge with scientific inquiry.

· Doesn't address challenges in translating traditional knowledge into modern medicine.

· Potential integration into modern medicine is acknowledged but not explored in depth.

· The study suggests a need for further research on the phytochemical composition of S. spinosa, but does not address the challenges associated with standardizing these analyses across diverse regions with varying climatic conditions and cultivation practices.

· The research gaps identified are somewhat broad and lack specificity, which may make it difficult for future researchers to design targeted studies that can fill these gaps effectively.

· The emphasis on oral administration as the primary method of application neglects the importance of understanding how different routes of administration might influence the bioavailability and therapeutic efficacy of S. spinosa compounds.

· There is little discussion on the preservation of indigenous knowledge in the face of modern development, which poses a threat to the long-term sustainability of traditional medicine practices.

Comments on the Quality of English Language

The English could be improved to more clearly express the research.

Author Response

Reviewer 1

 

Reviewer comment	How it was addressed
Title clarity	Line 2 – 4: The title was revised to: “Indigenous Knowledge and Utilization of Strychnos spinosa Lam. in Sub-Saharan Africa: A Systematic Review of Its Medicinal, Nutritional, and Cultural Significance”
Indigenous Knowledge (IK) and modern science	Line 39 – 42: The introduction now explicitly discusses how IK can complement modern science in addressing global environmental issues and supporting sustainable resource management.
Urbanisation and globalisation’s impact on IK	Line 42 – 51: The section highlights how urbanization and globalization impact the transmission of IK from older to younger generations, citing Mpofu and Miruka (2009).
Regional variations in S. spinosa utilisation	Line 151 – 156, 177 – 193:The Results and Discussion section explores how different African regions use S. spinosa for medicinal, nutritional, and cultural purposes.
Nutritional content and food security	Line 247 – 253: Expanded discussion on nutritional benefits and their role in addressing food insecurity.
Conservation status and sustainability	Line 78 – 86: The document now clarifies the IUCN Red List classification and discusses the risks of overharvesting and habitat destruction.
Recommendations for sustainable harvesting	Line 75 – 77: The paper suggests community-based conservation efforts, agroforestry initiatives, and formal cultivation as best practices.
Cultural significance	Line 155 – 156:  The cultural and spiritual roles of S. spinosa in various African communities were highlighted in Table 2.
Ethical involvement of local communities	Line 267 – 270: The study highlights the importance of engaging local communities in future research and benefit-sharing mechanisms.

 

Reviewer 2 Report

Comments and Suggestions for Authors

Reviewer 2 Comments
diversity-3462869-peer-review-v2
Article Title:
Indigenous Knowledge and Utilization of Strychnos spinosa Lam. in Sub-Saharan Africa: A Systematic Review of Its Medicinal, Nutritional, and Cultural Significance
-----------------    
Comments to authors#
Dear authors, 
This is a very interesting paper. The results are clearly presented, and the materials and methods have no serious flaws. 
Please consider my comments.
General report#
The scientific names are written with the authority at the first mention in the text only, after that the name of the genus is abbreviated and the name is written without the authority.
----------------------------------------
Point 1: Line 9: please remove the abbreviation from the abstract “ (IK)”, as it is sufficient to mention it in the introduction.
Point 2: Line 53: it will be great if you added a sentence about the taxonomy of Strychnos spinosa.
Point 3: Line 54: please add reference for the following sentence ‘commonly known as the 'bushman's poison tree' or 'kaffir orange…’ 
Point 4: Lines 61-85: Why do you write these paragraphs in red? It does not make sense, please turn it black.
Point 5: Line 192: Figure 2: Using a 3D pie chart in scientific articles is generally not recommended, please replace it with a 2D version.
Point 6: Line 216: replace ‘S. spinosa’ with “S. spinosa”, and make sure that the scientific names written italic within the MS. 
Point 7: Line 229: same above.
Point 8: Line 232: Figure 3, same above. 
Point 9: Line 255: The word indigenous should be capitalized in this context. 
Point 10: Line 283: replace ‘authenticate ethnobotanical’ with “authenticate the ethnobotanical” 
Point 11: Lines 56, 101, 293, 313 and 319: replace ‘Strychnos spinosa’ with “S. spinosa” 
Point 12: Line 316: replace ‘gastro intestinal conditions  and’ with “gastrointestinal conditions and” 
Point 13: References: the scientific names should be written italic, also remove the highlights.

Author Response

Reviewer 2

 

Reviewer comment	How it was addressed
Removal of abbreviation (IK) from abstract	Line 9 & 38: The abbreviation was removed from the abstract and introduced later in the introduction.
Taxonomy of S. spinosa	Line 55 – 56: A sentence was added to describe the taxonomy of S. spinosa Lam. (Loganiaceae).
3D pie charts	Line 194 – 195, 233 – 234: All 3D pie charts were replaced with 2D charts in Figures 2 and 3.
Scientific name formatting	Thanks for the comment, all scientific names were italicized consistently throughout the document.
References formatting	References were revised to ensure that scientific names are italicized.
Ethical considerations	Line 261 – 263, 324 – 329: Ethical aspects of Indigenous Knowledge sharing were added in the Discussion and Conclusion sections.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors propose the study titled " Economic and Environmental Sustainability of Olive Production: A Case Study Indigenous Knowledge and Utilization of Strychnos spinosa Lam. in Sub-Saharan Africa: A Systematic Review of Its Medicinal, Nutritional, and Cultural Significance". The topic is very interesting, the authors discuss around an interesting species Strychnos spinosa from Africa sites, used by local communities as medicinal, nutritional, and also as cultural point of view. The authors worked in systematic way exploring different electronic databases with 55 eligible studies that indicates as 37% of African countries have studied S. spinosa, mainly in Southern Africa, but many studies did not analyse the plant's nutritional and bioactive compounds. The research’s show that all parts of S. spinosa was used for different thinks, as Roots, bark, fruits, leaves and wood. These results and gap about nutritional and bioactive compounds, suggests quantitative research on its phytochemical properties and therapeutic applications within African traditional medicine. The manuscript are well written and argued. Only few suggestions after which the work can be published.

The suggestions in bold

 Introduction

• Lines 31-36. It is becoming increasingly clear that Indigenous knowledge systems (IKS) can play a critical role in environmental conservation [choose reference]. These systems contain a wealth of knowledge about local ecosystems, agro-ecosystems and sustainable resource management [2,3]. Indigenous people, who have lived in harmony within their natural surroundings for generations possess invaluable knowledge that can contributed to protection and preserving the environment [4,5], but unfortunately it is mainly the older generation that are the custodians of information;
• Line 46. Space [2],M;
• Lines 42-43. One main factor that influences this is the spread of urbanisation and globalization [choose reference];
• Line 56. Strychnos spinosa in italics Strychnos spinosa;
• Lines 87-88. This study is crucial for biodiversity conservation and sustainable natural resource management [Ben Mahmoud et al. 2024], as already started throughout the world especially in areas with highter plant biodiversity [Perrino et al. 2024…. choose other 2 references]

Add references

• Ben Mahmoud et al. 2024. https://doi.org/10.1007/s41207-024-00468-5
• Perrino et al. 2024. https://doi.org/10.1007/s00425-024-04571-3

2. Material and Method

Well done, few observations.

• Lines 97-98. I suggest to improve this period with the data-time in which the authors have been visited the sites and relative link on JSTOR, ScienceDirect, PubMed, and Google 97 Scholar was conducted;
• Figure 1. Is clear but please in legend refer that n is number of…..
• It would have been interesting to conduct some interviews with the locals, maybe with some photos. But I think it will be done in the future.

 

3. Results and discussion and 4. Research gap and limitations

Well done! the tables and figure are clear. No comments and suggestions

5. Conclusion

Some comments they are duplicated from the introduction

Comments on the Quality of English Language

no specific comments about quality of English language

Author Response

Reviewer 3

 

Reviewer comment	How it was addressed
Complementing IK with modern science	Line 88 – 90: The introduction now emphasizes how IK contributes to biodiversity conservation and can complement modern scientific approaches.
Literature search dates	Line 100: The Materials and Methods section now specifies that the search was conducted between April 2024 and January 2025, enhancing transparency
Search terms	Line 101 – 103: The search terms, including “Indigenous knowledge,” “socio-ecological impact,” and “phytochemical analysis”, were specified in the methods section.
Community involvement	Line 242 – 245, 258 – 263: The discussion now highlights the importance of involving local communities in future research and conservation initiatives.
Research gaps	Line 265 – 275: A dedicated section outlines research gaps, including the need for phytochemical authentication and sustainable harvesting practices.

 

 

 

 

 

General Improvements Across All Reviewer Comments

 

Area	Improvements made
PRISMA Reporting	Line 104 – 105:Clear explanation of the inclusion criteria and search methodology following the PRISMA 2020 Statement.
Language inclusivity	Line 266 – 270: Addressed potential language bias by recommending future inclusion of studies in local languages.
Conservation framework	Line 75 – 77, 88 – 90: Proposed community-based conservation models and suggested drawing examples from other regions.
Socio-ecological impacts	Line 239 – 263: Highlighted the socio-ecological impacts of harvesting S. spinosa and the need for further investigation.
Research limitations	Line 266 – 311: Discussed methodological limitations and provided recommendations for future studies.
Typographical/ mechanical errors	All highlighted errors, including issues related to spacing, spelling, grammar, and any necessary deletions or additions, have been thoroughly corrected throughout the document.

 

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I did not find the highlighted text in the revised version. It would be better if the authors uploaded the highlighted revised manuscript.

Comments on the Quality of English Language

The English could be improved to more clearly express the research.

Author Response

Dear Reveiwers,

Thanks for the comments we have revised all the comments. We have attached rebuttal for your attention.

Author Response File: Author Response.docx

Round 3

Reviewer 1 Report

Comments and Suggestions for Authors

In Table 1, under the "Identification" section (n=1924), please include the names of the databases searched to enhance transparency and provide a clear understanding of the data sources.

Additionally, it is unclear why major academic databases such as Scopus, Web of Science, and Wiley were not included in the literature search. These databases are widely recognized for their high-quality scientific literature, and their exclusion should be justified. If these sources were intentionally omitted due to specific criteria, please provide a clear rationale in the manuscript. However, if they were overlooked, I strongly recommend conducting an additional literature search in these databases to ensure a more comprehensive and unbiased dataset. The results from this expanded search should be systematically integrated and reflected in Table 1. Also, if new data is added, please make sure that the total number of identified records (n=1924) is updated accordingly. Addressing these points will strengthen the study’s methodological transparency and ensure a more rigorous literature review.

The authors mention "for treatment of different ailments" in Figures 2 and 3, but they do not provide a visual representation of the specific ailments being treated. To improve clarity and enhance the understanding of the study, I recommend including an additional figure that categorizes and visually represents the different ailments mentioned in the text. This new figure could be structured as a bar chart, pie chart, or other showing the frequency or percentage of ailments treated, categorized by type (e.g., respiratory diseases, gastrointestinal disorders, skin conditions, etc.). Providing such a figure will make the findings more accessible and visually informative for readers.

The manuscript would benefit from a dedicated section discussing the economic importance of the species under study. This section should highlight its commercial value, potential applications in pharmaceuticals, traditional medicine, agriculture, or industry. Additionally, if the species has economic significance in terms of trade, cultivation, or sustainable use, providing relevant data or examples would enhance the study's impact. Integrating this information will offer a broader perspective on the species' relevance beyond its medicinal applications.

Comments on the Quality of English Language

 The English could be improved to more clearly express the research.

Author Response

Rebuttal on Addressing Reviewer Comments

 

The updated document reflects a comprehensive effort to incorporate the feedback from the reviewer. Below is a summary of how each  comment was addressed:

 

 

Reviewer comment	How it was addressed
In Table 1, under the "Identification" section (n=1924), please include the names of the databases searched to enhance transparency and provide a clear understanding of the data sources.	Thank you for the insightful feedback regarding Figure 1 in the manuscript. We acknowledge the importance of explicitly stating the databases searched. In response to your suggestion, we have update the “Materials and methods” section to include the names of the databases that were systematically searched. These include: Google Scholar, JSTOR, PubMed, ScienceDirect, Scopus, Web of Science and Wiley.
Additionally, it is unclear why major academic databases such as Scopus, Web of Science, and Wiley were not included in the literature search. These databases are widely recognized for their high-quality scientific literature, and their exclusion should be justified. If these sources were intentionally omitted due to specific criteria, please provide a clear rationale in the manuscript. However, if they were overlooked, I strongly recommend conducting an additional literature search in these databases to ensure a more comprehensive and unbiased dataset. The results from this expanded search should be systematically integrated and reflected in Table 1. Also, if new data is added, please make sure that the total number of identified records (n=1924) is updated accordingly. Addressing these points will strengthen the study’s methodological transparency and ensure a more rigorous literature review.	We acknowledge the concern regarding the omission of significant academic databases in our original submission. However, after reviewing our methodology, we confirm that these databases were indeed searched as part of our literature identification process, but were not all explicitly listed. We have thus explicity stated these databases, as advised above, in the “Materials and methods” section. We regret any unintentional omission in describing our search strategy and have clarified this in the revised manuscript. Any further relevant studies identified through any expanded search in these databases, would have been systematically incorporated and we would have adjusted the total number of identified records accordingly.
The authors mention "for treatment of different ailments" in Figures 2 and 3, but they do not provide a visual representation of the specific ailments being treated. To improve clarity and enhance the understanding of the study, I recommend including an additional figure that categorizes and visually represents the different ailments mentioned in the text. This new figure could be structured as a bar chart, pie chart, or other showing the frequency or percentage of ailments treated, categorized by type (e.g., respiratory diseases, gastrointestinal disorders, skin conditions, etc.). Providing such a figure will make the findings more accessible and visually informative for readers.	We appreciate the reviewer’s valuable suggestion to enhance the clarity of our findings by providing a visual representation that categorises the different ailments treated with S. spinosa. In response, we have included an additional figure illustrating the frequency and categorisation of ailments treated using various parts of S. spinosa. We have created a new bar graph (Figure 4) to illustrate the percentage distribution of ailments treated, such as: gastrointestinal disorders (e.g., diarrhea, stomachaches, vomiting), infectious diseases (e.g., malaria, bacterial infections, tuberculosis), pain and inflammation-related conditions (e.g., fever, hemorrhoids, swelling), reproductive health issues (e.g., dysmenorrhea, infertility, miscarriage prevention), skin-related conditions (e.g., wounds, foot crevices, dermatitis), respiratory conditions (e.g., respiratory deficiencies) and other traditional uses (e.g., spiritual rituals, snake bites, cardiovascular issues). This new figure is accompanied by a description in the “Results and discussion” section, summarising the key findings and providing insight into the most commonly treated conditions with S. spinosa.
The manuscript would benefit from a dedicated section discussing the economic importance of the species under study. This section should highlight its commercial value, potential applications in pharmaceuticals, traditional medicine, agriculture, or industry. Additionally, if the species has economic significance in terms of trade, cultivation, or sustainable use, providing relevant data or examples would enhance the study's impact. Integrating this information will offer a broader perspective on the species' relevance beyond its medicinal applications.	We appreciate the reviewer's insightful suggestion regarding the inclusion of a dedicated section on the economic importance of S. spinosa. In response, we have incorporated a new section discussing the commercial, pharmaceutical, agricultural, and industrial applications of the study species. This addition highlights its potential economic significance in trade, cultivation, and sustainable use, thereby broadening the study’s impact beyond its medicinal applications.

 

Author Response File: Author Response.docx